Fluorescent lighting unit



20, 1946- J. E. HOLMES FLUORESCENT LIGHTING UNIT Filed March s, 1944 s Shets-Sheet 1 Au 20, 1946. J. E. HOLMES 2,406,146

FLUORESCENT LIGHTING 1mm Filed March 8, 1944 5 Sheets-Sheet 2 Aug. 20, 1946. r J. E. HOLMES 294069146 FLUORESCENT LIGHTING UNIT Filed March 8, 1944 3 Sheets-Sheet s Patented Aug. 20, 1946 UNITED STATES PATENT OFFICE FLUORESCENT LIGHTING UNIT John E. Holmes, Auburndale, Mass. Application March 8, 1944, Serial No. 525,532 1 Claim. (01. 176-122) This invention relates to fluorescent lighting units.

The invention has for an object to provide a fluorescent lighting unit of novel and improved construction characterized by the provision of a luminous surface of extensive area as distinguished from the conventional elongated tubular fluorescent lamps now in use.

With this general object in view, and such others as may hereinafter appear, the invention consists in the fluorescent lighting unit, and in the various structures, arrangements and combinations of parts hereinafter described and particularly defined in the claim at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention, Fig. 1 is a cross-sectional view of a fluorescent lamp embodying the present invention; Fig. 2 is a plan View in cross section taken on the line 2--2 of Fig. 1; Fig. 3 is a cross-sectional view similar to Fig. l, illustrating a duplex form of the-present lighting unit; Fig. 4 is a plan view of the lamp shown in Fig. 3, portions being broken away and shown in cross section; and Figs. 5 to 13 are diagrammatic'views of various different shapes of lamps in which the present invention may be embodied.

In general the present fluorescent lighting unit includes a pair of electrodes which are spaced apart and connected by a long, non-opaque tube made up of a large number of closely spaced sections and containing any usual or preferred gases of the general type now used in commercial fluorescent lamps, and the interionof the tube is provided with a fluorescent coating, whereby to provide a luminous surface of substantial continuity and relatively large area. In one form of the invention the relatively long tube maytake the form of a spiral with convolutions contiguous to one another. In another form of the invention the tube may comprise a plurality of straight sections with successive sections connected at alternate ends whereby to provide a zigzag path through which the discharge is caused to take place in passing from one terminal-to another. Other forms of the invention will be more fully hereinafter described including a multiple unit structure.

Referring now to the drawings, Figs. 1 and 2 illustrate the present invention as embodied in a fluorescent lighting unit comprising a gaseous electric discharge lamp of a substantially flat,'circular disk shape and includes a casing or envelope, indicated generally at I0, having substantially flat spaced upper and lower-walls 12,14

2 respectively and an annular rim lijoiningthe peripheral edges of the walls 12, [4 to form a flat disk shaped chamber. One of the walls, M of the casing. lll'is formed of glass or other non-opaque material and preferablythe casing Ill is composed entirely of glass. A tubular stem 18, which maycomprise a section of standard round tubing, may be fused to the center of the casing or envelope in communication with the interiorthereof and provided at its free end with an electrode 20. A second tubular stem 22 operatively connected adjacent the marginal portion I6 of the casing is provided at its end witha second electrode 24. As herein shown, a continuous spirally extended web or rib 26 starting at the center of the envelope l0 adjacent'the electrode'stem l8'and ending at the outer rim of the casing adjacent the electrode stem 22 extends between the upper and lower walls I2, I4 and forms a continuous spiral chamber or passageway 28- of substantially uniform cross section connecting said electrode tubes 18, 22 as clearly shown in Fig. 2. A fluorescent coating 30 of any usual or preferred composition is provided on at least the non-opaque walls l2, l4 and preferably the interior surfaces of the spiral chamber throughout the length thereof are coated with the fluorescent coating. A suitable gas'together with a small quantity of mercury vapor is sealed v Within the casing according to the usual practice followed in the production of the commercial fluorescent lamps now on the market;

In operation, upon the application of asuitable potential across the terminals, ionization of'the gas occurs with a resulting discharge between the electrodes, such discharge following the spiral path 28. In accordance withthe well-known principles of operation of fluorescent lamps, the discharge vaporizes the mercury which sustains the arc between the electrodes generating invisible ultra-violet radiations which in turn excite the fluorescent coating to convert the latter into visible sources of light to be transmitted through the non-opaque wall or walls of the casing. The adjacent sections of the spiral passage 28 are disposed sufficiently close to one another to cause the exterior surface or surfaces of the present fluorescent lamp to present a continuous luminous surface of substantial area when viewed from the top or bottom of the unit.

The electrodes 20, 24 may be of any standard type now employed commercially, being coated with a suitable electron emitting material and as herein shown, 'theends of the electrode tubes [8-, Rare provided with'caps 32, 34 for insertion 'will be seen that when canopy 44 mayand preferably will be mounted over the transformer, as shown, the canopy being supported between lock nuts 46 on the pendant tube 42. In order to support the weight of the lamp, the upper wall I2 thereof may be provided with a plurality of eyes 48 cast thereto, and

through-which suitable hangers 50 may be extended. The hangers. 56 may be conveniently attached to the rim of the canopy 44, as illus-' trated.

The casing or envelope I may andpreferably Will be made of a lead glass and is preferably slightly dished, as illustrated, so that when the 4- 86 and thence .through the second spiral path to energize both fluorescent lamp sections.

With this construction, it will be apparent that in a duplex unit as described many different combinations of colored lighting effects may be obtained by providing the individual casings or envelopes with fluorescent coating materials of dilferent compositions, or, if desired, one of the envelopes may comprise a bactericidal unit in which event the envelope may be made of a glass having special transmission characteristics, 7 such as a quartz glass.

In the illustrated embodiment of the invention shown in Fig. 3, the upper envelope 62 may be fluorescent coating fluid is introduced through the f outer electrode opening, prior to fusing of thetubular stem 22 thereto, the fluid will drain evenly .to theicenterof the spiral. Thereafter, the en- 'velope may be turned over to permit the fluid to flowback, coating the opposite face of the ene velope, the excess fluid being drained out through the same opening. I

It will be understood that the present fluores- Icent lamp structure may be adapted for either hot or cold cathode operation and that it may be made in a wide range of sizes as for example from a minimum of approximately four inches in diameter to a diameter of approximately ten feet. Likewise, the cross section of the spiral path defined by the distance between the upper and'lower walls I2, I4 and the distance between adjacent web portions 26 as'viewed in cross section in smaller in diameter than the lower envelope and, as herein shown, the outer edge or rim 90 of the envelope 62 retains its spiral outline throughout, thus enabling a substantially uniform crosssectional area of the path 68 to be maintained.

Fig. 1, may vary within wide limits in accordance with -thenumber of lumens desired, the capacity of the transformer 40 and the current intensity being determined accordingly. .The present unit may also be made to transmit any desired color of .light as determined by the composition of the the art. 7

' Referring now to Figs. 3 and'4, as h'ereinillusgfluorescent coating material as is well known in trated, the present invention may be embodied in a a duplex design having a lower lamp section 69 similar in structure to that above described and a second section 62 disposed above the first section-.-- Thesecond casing or envelope 62 is also iprovidedwith a spirally'extended web 66 between theispaced upper and lower walls thereof to form a spiral passage68 within the casing. The central portion ofv therca-sin 62 maybe provided withjan opening 76 through which a tubular stem 1 :72 extending from the center of the lower unit 613 projects, as illustrated, the outer end of the tube being provided with an electrode 14. A sec- 78 extends from and is .operatively connected to the inner end of the spiral passage 68in the upper lamp section. The outer ends of each of the spiral passages 64, 68 are connected by a glass tube 80 which is provided with ajsolid glass, section 82 intermediate the ends thereof to form a gas dam between the two sections 60, 62. A pair of electrodes 84, 86, disposedonopposite' efiected'iscaused to move between the electrodes through one of the spiralpaths64, 68, then through the electrically 'connectedelectrodes 84,

The upper and lower lamp sections 6@, 62 may and preferably will be connected; by solid glass lugs 92 and the entire unit may be supported by hangers inserted through the glass eyes. 94 cast to the upper wallof the lower unit 66, as shown.

A large number of variations of the present fluorescent lamp may be provided, a few of which are diagrammatically illustrated in Figs. 5 to 13 inclusive. All such modifications are characterized by a structure wherein adjacent sections of the discharge path. are-disposed, suiflciently near to one another to impart a luminous surface of substantial area. Figs. 5 to 10 inclusive comprise variations of the unit shown in Fig.1, each having a spiral path extending from the center to the outer rim of the envelope thus' lustrated in Figs. 5 to .10 include cylindrical, cone,

dome and dish-shaped forms or variations thereof and which may be upright or inverted. These various shapes may also be .made rectangular 3 in plan as well as cylindrical.

' ond tubular stem I6 provided with an electrode Another form of easing or envelope structure is diagrammatically illustrated in Fig. 11,- which shows a substantially flat rectangular envelope we having a plurality of baiiles I62 arranged to cause the discharge between the electrodes I 04, 896 to follow a substantially zigzag or spiral path, back and forth around the ends of the bellies to eifect transmission of visible light over an extensive flat area. 7

Fig. 12 illustrates aspherioal adaptation I88 of. the present lamp structure, provided with bafiles I If! for directin the discharge between electrodes i 52, IM, through a substantially spiral path formed between the walls of the sphere, the center being hollow, thus forming a luminous globe.

A furthermodification of the present fluorescentlamp, as diagrammatically illustrated in Fig. 13, comprises a hollow elongated cylindrical structure I I6 with vertical walls and having elongated baffle plates of substantially. uniform between the electrodes H6, I22 are directed. While the preferred embodiment of the inven-fl tion ha been herein illustrated and described, it

will be, understood that the invention may be embodied-in other forms within the scope of the following claim.

Having thus described the invention, what is 1 claimed is MAI-fluorescent i htin comprising? a IIS forminga zigzag path cross section through 1 which the radiations resulting from the discharge 1 closed enerally circular disc-shaped casing having flat upper and lower walls spaced apart a distance so that the diameter of said casing is substantially greater than its height,'at least the lower of said walls being of a light conducting material; a continuous partition member extending between said upper and lower walls and arranged so as to form a spiral chamber within said casing containing an ionizable gas, one of the ends of said spiral chamber being positioned substantially at the center of said casing and the other adjacent the periphery thereof; and a pair of hollow extensions communicatin with each end of said spiral chamber and extending in a direction substantially parallel to the upper wall of said casing and adjacent thereto to points relatively closely spaced and symmetrically located with respect to the centerof said disc-shaped casing, said extensions terminating in upwardly extending parallel electrode containing portions substantially perpendicular to the upper wall of 10 said casing.

JOHN E. HOLMES. 

